Underfeed furnace.



R- S- RILEY.

UNDEHFEED FURNACE.

APPLICATIQN FILED OCT. 20. 191|.

Patented Aug. 3, 1910.

2 SHEETS-SHEET 1.

Mmm I l Z R. S. RILEY.

UNDERFEED FURNACE.

APPLICATION man ocT.20. 1911.

Patented Aug. 3, 1915.

2 SHEETS-SHEET 2.

'1111111'IlllIllIllIllll/l/ .v

U IV/ UNITED STATES PATENT OFFICE.

ROBERT SANFORD RILEY, OF PROVIDENCE, `RHODE ISLAND.

UNDERFEED FURNACE.

Application led October 20, 1911.

To all whom it may concern Be it known that I, ROBERT SANFORD RILEY, acitizen of the United States, and resident of Providence, inthe countyof Providence and State of Rhode Island,haveV invented certain new anduseful Improvements in Underfeed Furnaces. of which the following is aspecification.

The present invention relates to. furnaces of the underfeed type and hasfor its object to combine in a furnace of this type together withmechanism for automatically feeding fuel into the furnace to a pointtherein where the supply of air is wholly lacking or is insuflicient tosupport combustion, an additional positively-acting means .for effectingfeed of burning fuel and refuse to the part of the furnace at which therefuse is discharged.

Other objects are to out away and break off deposits of slag and clinkerwhich have a tendency to form on the inclosing walls of the furnace, tobreak up lumps of coke and clinker in the fuel bed, making such bedhomogeneous in condition and preventing formation of holes therein, andto provide improved and more eficient means for supplying air to thefurnace to support combustion.

In the main, the objects sought and attained by the present inventionare the same or are similar to those accomplished in other forms offurnace shown and described in applications filed concurrently herewith,Serial Numbers 655,821 and 655,823.

The features which distinguish this invention from those shown in theapplications referred to relate to a particular construction and mannerof operation by which each retort, including its bottom and side walls,moves as a unit; to the manner in which the retort moves; to aparticular form of fuel feeder; and to details of construction and ofmechanism for operating the movable parts, hereinafter more particularlydescribed. In the particular embodiment of my invention illustrated inthis application, the retort walls move in a generally up and downdirection and with oscillatory motion.

In the accompanying drawings forming a part of this application: Figurel represents a longitudinal section of a furnace showing the partsthereof in which the further invention' is embodied, and omittingstructural details which are not essential to .Specification of LettersPatent. p Patented Allg. 3, 1915.

serial No. 655,822.'-

is a vertical cross section of two retorts taken on line 1- 4c of Fig.l. Fig. 5 is a longitudinal sectionv of one of the air conduits whichforms a side of the retort, such section being taken on line 5-5 of Fig.2. Fig. 6 is a cross section of one retort taken on line 6-6 of Fig. 1.Fig.*7 is an elevation of one of the hollow bars which form a part ofthe air-supplying means and fuel support.

Referring to the drawings-the numeral l indicates the front wall of afurnace inclosure, 2 represents a bridge wall, and 3 represents an airbox or trunk extending from side to side of the furnace and serving bothas a support for the retort or retorts and as a conduit for conveyingthe air necessary to support combustion to the furnace. The side wallsof the furnace inclosure and the base by which the furnace as a whole issupported are omitted as not being necessary t'o convey an understandingof the essentials of my invention. Any sort of base or supportingstructure may be designed, in accordance with the requirements of thesituation in which the furnace is to be installed.

Thepart of the furnace which holds the fuel consists of a retort or aplurality of retorts in which the fuel is first distilled withcombustion of its volatile constituents, and in which the liXed carbonis converted into coke. Each of these retorts is composed of a bottomand a pair of double-Walled sides through which air is caused to flowand which constitute air conduits. The bottom of the retort is a plate 4which eX- tends through the front of the furnace, a part being withinthe furnace inclosure. The forward or outer end of the bottom plate isconnected with a tubular fuel guide or conduit 5 on the top of which isa hopper 6 containing a supply of fuel. The hopper opens at, its bottominto the upper part of the fuel conduit. The retort bottom is supportedby a semicylindrical box 8 secured to the air trunk 3 on the upper sidethereof.

The front wall 9 and the rear wall l0 extend downwardly from the underside of the bottom plate and bear on the sides of the semicylindricalbox, the wall 9 bearing directly against the box and the wall 10 havinga projection 11 for this purpose. At the sides of the bottom plate aredepending side walls 12 which have concave edges fitting about thesemicircular end walls 13 of the box 8. Thus, the walls 9, 10 (withitsextension 11), and 12, form an inclosure which fits about thesemicylindrical box 8 and is in practically airtight contact therewith.The box 8 is open at its bottom, in registry with an opening in theupper side ofthe air trunk, and also has openings in its `side wallscommunicating withthe interior of the box above described. Rising abovethe bottom plate 4 are side walls 14 across which extends a top wall 15.These walls merge with the corresponding walls of the fuel conduit 5 anddefine the rear end of this conduit and the forward end or beginning ofthe retort. The double-walled conduits which form the sides of theretort at the inner end thereof and are contained within the furnace areindicatedby 16 and 17 respectively. They are secured to the wall 10,previously mentioned, by means of flanges 18 and bolts 19, and extendabove and bebelow the bottom plate 4. Their.v interior openings registerwith openings in the wall 10 and thus communicate with the air trunk.The walls of the conduits 16 and 17 where they rise above the bottom 4register with the walls 14, which also are double. Across the spacebetween'the double walls 14 is a web 20, shown in Fig. 5, which limitsthe height of the space between these double walls into which the airmay flow.

The conduits 16 and 17 are open at their upper edges, andfmountedthereon are boxes 21 which have walls at the top, front and oppositesides, but are open at the bottom and rear sides. Their side walls arespaced so as to correspond with the inner and outer walls 22 and 23respectively of the air conduits, as shown in Fig. 6. The boxes areplaced in series, close together, with the side walls of each in contactwith the front wall of the next. Thus the boxes form compartmentscommunicating with the conduits into which air may pass from the latter.The rear side of the box is somewhat longerthan the front wall, hencewhen they are placed in series as shown in Figs. 1 and 5, the open rearside of each box is almost entirely closed by the front wall of the nextadjacent box, there being only a narrow slit left uncovered. The airwhich enters the boxes may be discharged through these slits across thespaces within the furnace at the sides of the retorts and betweenadjacent retorts. Thus the series of boxes assembled and forming theslits as described, form nozzles arranged to direct the air forsupporting 'combustion into the furnace in the manner required. The topof each of the boxes is provided with a lip 24 extending over this slitand to some extent overlapping the top of the next box and having thefunction of deflecting the air which issues from the slit and causing itto flow horizontally through the fuel before its velocity is expendedand it rises.` In the inner side Walls, also, of the' boxes 21 areorifices 25 through which the air may flow across the retort. The boxesrest upon the upper edges of the walls of the air conduits and areprevented from dislodgement by hooks 26, each box having a hookprojecting to some extent into the conduit on-which it is mounted andengaging a bar 27 which crosses the conduit.

The upper edges of the conduits 16 and 17 are inclined to the directionof the bottom 4, consequently the latter crosses the plane of theseedges and also the line of outlet boxes 21 which follow and arepositioned by the conduit edges, and the bottom plate termi-y natesshort of the inner ends of the conduits. In all those parts of thelatter which project beyond the bottom plate, I mount transverse barswhich support the fuel after it leaves the bottom plate 4 and at thesame time supply air thereto. Such bars are designated at 28, and one ofthem is shown in rear elevation in Fig. 7. They are sufii ciently longto extend across the space between the conduits 16 and 17 and rest uponthe upper ends thereof. They are preferably the same in cross section asthe boxes 21, with the exception that between their ends they areprovided with bottom walls 29. They are open at the rear sides, however,throughout their entire length, and their top walls are provided withlips 30 also extending throughout the entire length of the bars. At theends which overlie the conduits 16 and 17 the bottoms of the bars areopen to establish communication with the conduits, and at these ends aredepending hooks 31 similar to the hooks 26 which secu're the bars inplace in the same way that the boxes 21 are secured. The bars 28 areassembled in the same manner as the boxes 21 and bridgel the -spacebetween the conduits up to the end of the bottom plate 4. The lip 30 ofeach bar overlies the top of the next adjacent bar to the rear; and suchlips, together with the top walls from which they project, support thefuel discharged from the retort bottom 4. They form a series of steps onwhich the fuel rests and between which air is discharged into the fuel.

In the fuel conduit 5 is a pusher 32 adapted to pass back and forthunder the outlet of the hopper 6 and having an extension 33 lying alongthe bottom plate 4 and projecting into the retort. Rising from thisextension are shoulders 34 and 35 which are abrupt at the rear andformed with a very gradual slope on the front side. A plate or shoulder36 is fixed to the wallsl of the fuel conduit and extends across the*extension 33. Its purpose is to prevent the fuel from being withdrawnwhen the pusher is retracted,l and it is therefore termed a fuel stop. n

It will have been seen from the foregoing description that the entirestructure of each retort, including the fuel conduit, hopper, and airconduits which form the retort walls, is a unit which is supportedentirely by the semicyli'ndricalbox 8 above the air trunk. This entirestructure is thus able to move oscillatively about the axis of the box 8which serves as a pivot. When moved in this manner, the rear part of theretort and the bars 28 are raised and lowered, while the sides of theretort and the air boxes near the forward end thereof move up and downand also somewhat forwardly and rearwardly, as these parts of the retortare above the axis of oscillation. The top wall l5 of the fuel conduitis concentric with thev axis of oscillation, and a fixed plate 37concentric therewith and making contact with such plate, is secured tothe furnace wall to provide a seal against escape of fuel and connedair. Secured to the rear ends of the conduits and extending across thespace between them is a plate 38, also curved concentrically with theaxis of oscillation, which may be termed an ash shield. A. plate 39crosses the space between the bridge wall 2 and this ash shield, for thepurpose of supporting refuse and permitting discharge of the same as therefuse accumulates.

A suitable mechanism for both reciproeating the pusher 32 andoscillating the entire retort, consists of a shaft 40 having a crank pin41 provided with a block 42 which is adapted to slide in a slotted head43 secured to the pusher. This shaft, in rotating, moves the pusher backand forth in a manner well understood, and as the length of the slot isless than the throw of the crank, the crank-pin block whichengages thealternate ends of the slot raises and lowers the cross headcorrespondingly and thereby swings the retort. It may be desirable toadjust the amount of oscillation of the retort, and for this purpose Iprovide a stop 44 in the slot and an adjusting screw 45 by whichit maybe raised and lowered.

The operation of the furnace or stoker is as follows: lVhenever thepusher is retracted from the furnace it uncovers-the outlet of thehopper, allowing a quantity of fuel it further int-o the retort. Thestop 36 holds the fuel from being pushed back by the shoulder 34 andinsures a progressive flow of fuel. A similar effect further in theretort is secured by the shoulder 35. As the pusher travels in a linecrossing the retort mouth and is located partly below and partly infront of the line of air-admission, or, in other words, as theadmissionof air occurs between the path in which the green fuel is fedand thesurface of the fuel bed, the equivalent of an underfeed of fuelinto the furnace is eiected. The green fuel,

'when it first enters the retort, is below the The movement of theretort4 and its walls is provided to effect a gradual feed of theburning fuel and refuse to the discharge point. The mouth of the retortis somewhat sloping but the slope is less than that down which granularor powdered material such as fuel and its refuse will slide under theinfluence of gravity. The up and down movement of the rear part of theretort, and the forward and back movement of the retort walls at thefront of the furnace, cause the fuel to be raised and lowered and at thesame time gradually forced to the rear. The pusher extension movestoward the rear of the furnace when the retort is rising, and the retortwalls move, in effect, upwardly and forwardly, that is, oppositely tothe fuel during this movement, and they pro-- pel the fuel toward therear during the downward and rearward movement. The fuel on top of theair boxes and bars is progressively pushed from one to the otherrearwardly until the residue, consisting mainly or wholly ofincombustible refuse, is deposited on the dumping plate 39.

Ordinarily there will be two or more retorts of this character mountedin one furnace, arranged so that the adjacent retorts movesimultaneouslyin opposite directions, either of two adjacent retorts being elevatedwhile the other is lowered. To obtain this effect, the cranks whichactuate the adjacent retorts are set opposite to each other, as shown inFig. 3. Each two contiguous retorts, moreover, a re so connectedtogether as to counterbalaruzc one another and thereby relieve theengine or motor which actuates the retorts from the necessity ofperforming any more work than merely sufficient to overccjae friction.

vin the hopper.

The manner of mounting the retort structure is such that the weight ofthat part which projects into the furnace with its load of fuel. isgreater than the weight of the forwardly projecting part and the fuelConsequently the action of gravity tends to lower the retorts, and thistendency is overcome by the power acting through the shaft 40. I havedevised a means, consisting of a beam 46 pivoted upon a fixed standard47, and links 48 and 49 connected to opposite ends of the beamrespectively and to the forwardly projecting fuel conduits, throughwhich the force of gravity acting on the elevated retort tends to raisethe lower retort.

In addition to the advantage, above described, arising from theprovision of two or more retorts actuated simultaneously in oppositedirections, this'arra-ngement also more efliciently accomplishes therearward feed of the burning fuel and ash. For when one retort is raisedand the adjacent retort is lowered, the fuel which is piled up over thewalls of the elevated retort and which is continually pushed upward andto the rear by the feeding pusher, overflows and falls upon the fuel bedcarried by the adjacent depressed retort, being thus alternately thrownfrom one to the other until it is finally worked off from lthe' ends ofthe retorts on to the dead plates.

- Where more than two retorts are combined in one furnace, thearrangement of cranks is such that the two retorts on opposite sides ofany intermediate elevated retort are both depressed. Any retort thuscarries its own section of the fuel bed independently of the sectioncarried by the adjacent retorts, and such sections are alternatelyraised and lowered. The fuel is thus kept in continuous agitation and isbroken up into comparatively small pieces.' At least, the formation ofexcessively large lumps of either coke or clinker is prevented. Thus theformation of holes in the fuel bed is prevented, because the lumps arebroken up into pieces small enough to fall into any such holes andprevent loss of air through such holes or thin places and diversion ofthe air from thicker parts of the fuel bed. The retort walls in aoneretort furnace, and correspondingly the outer walls of the outermostretorts in a furnace having more than one, travel close to the sidewalls of the furnace and are enabled b v virture of their movement tostrike and cut or break away any lumps of fuel or slag which may fuse onsuch side walls. In a similar manner, lumps of slag or clinker which mayaccumulate on the front wall arc broken away by the pressure given tothe fuel adjacent this front wall by the same movement. Much trouble hasbeen experienced in furnaces having stationary grates and retorts, byreason of accumulation of clinkerv on the walls and the difficulty ofremoving the same.` In my furnace, however, when such deposits ofclinker have formed, they are either struck or pressed upon by the partsof the retort structure or by the fuel and thus broken awav.

In the foregoing description of operation, where I have used the wordretort I have had in mind the entire portion of the retort structurewhich lies within the furnace inclosure, including the horizontal barsover which the fuel is fed, as well as -the retorts proper consisting ofthe spaces between the upright conduit walls and the air boxes 21, andabove the bottom plate or floor 4.

Each of the vretort structures is an independent unit and may be usedalone in a narrow single-retort furnace, or together with others in awider furnace. The outermost side walls of each retort are vertical,without external projections, and so the retort may be placed betweenthe smooth side walls of the furnace built the proper distance apart.There are no impervious fuel-supporting surfaces between the outermostwalls of the adjacent retorts or between such retort walls and thefurnace walls, but, instead, such spaces as may exist between theretorts, and such spaces are appreciable because the retort walls arenot smoothly finished, are open, and allow air to flow from beneath theretorts into the furnace in consequence of the partial vacuum which isalways present under ordinary working conditions in a furnace.

The tops ofthe air boxes and bars on which the fuel discharged from theretort rest-s, are not impervious fuel-supporting plates but correspondrather to grate bars between which spacesare left for the passage of airinto the fuel bed.

The retort structure is very simple, and, except for the air boxes andbars, consists of a very small number of parts,-as here shown, exactlyfour. These parts can easily be assembled either at the factory or atthe place where the furnace is erected, by simplv bolting the conduits16 and 17 to the main part and bolting the shield 38 to the ends of theconduits. Such parts may be put together anywhere, and the requirednumber of retorts thus made mounted side by side in the furnaceinolosure. The air boxes 21 and bars 28 are respectively duplicates ofeach other and may be made cheaply and in large quantities and appliedupon the retort structures to the number required.

Although I have illustrated the oscillating retort structure as being aunit, the side walls, Hoor and rear extension grate being rigidlyconnected together and moving in unison, -yet I desire to state that myinvention in its broader aspects is not limited to this feature but ispresent as well in a construction where the floor is stationary and thesides and extension grate oscillate, and also in a construction wherethe fioor and extension grate are both stationary and the sides aloneoscillate.l Such a construction is illustrated in oneof the co-pendingapplications hereinbefore referred to, namely, No. 655,823 and iscovered in some of the broader claims of this. application.

Having thus explained the nature of my said invention and described away of constructing and using the same, although withoutattempting toset forth all the forms in which it may be made or all the modes of itsuse, what I claim is:

l. In a furnace, a fuel burning retort consisting of a bottom imperviousto the passage of air and side walls at each side of said bottom, saidwalls being mounted with capability for upward and downward movementatone end, means for constantly feeding 4fuel into the retort at one endthereof, and means for giving the defined movement to said walls toeffect a gradual progression of fuel and refuse through and from theretort. i

2. In a furnace, a fuel burning retort consisting of a bottom and sidewalls extending from one of the boundaries of the furnace i into thefurnace, said side walls having airemission outlets arranged to directair across the retort-and being mounted to oscillate about a horizontalaxis near said boundary, whereby the portions of the walls within thefurnace are capable of moving upwardly and downwardly, and mechanism forsoy moving said walls continuously to effect a progressive travel offuel from the retort into the furnace.

8. In a furnace, a plurality of fuel burning retorts mounted side byside, each including in itsiconstru ction upright side walls,

and a fuel passage between the walls, said,

walls having air-emission outlets arranged to direct air across thepassage, andsuch walls of one retort being mounted with capability formovement relatively to the walls of the other oscillatively about ahorizontal axis transverse to the direction of the retorts located nearone boundary of the furnace, and means for oscillating said relativelymovable walls simultaneously and oppositely, to effect a progressivefeed of the fuel from the retorts into the furnace.'

4. In a furnace, a fuel-burning retort including in its constructionseparated airconduits which form the walls of the retort and a bottombetween and below the upper limits of said conduits, said conduitshaving air outlets `above the floor arranged to direct air across theretort, supporting means for said conduits near the front of the furnaceon which the conduits are mounted to swing about a substantiallyhorizontal axis, and means for swinging said conduits about such axis.

5. In a furnace, a fuel-supporting floor, air conduits at each side ofsaid floor and having air outlets above the floor, forming the sides ofa fuel burning retort, hollow bars extending across between the conduitsbeyond and below the end of said floorihaving outlets for air, and meansfor raising and lowering said conduits at an end thereof to effect afeed movement of the fuel.

6. In a furnace, conduits adapted to supply air to the furnace extendingfrom the front toward the rear thereof and separated from one another,having air outlet near the upper limits, a plate extending between theconduits forming the floor of the retort of which said conduits are thesides, said floor extending in such a direction as to intersect theupper edges of the conduits between the ends thereof, andfuel-supporting plates extending between the conduits beyond and belowthe end of said fioor having spaces between them4 adapted to permitpassage `of air, said conduits and plates being movable upwardly anddownwardly to eect a progression of fuel.

7. In a furnace, an air trunk, a cylindrically-formed support mountedupon said air trunk and having passages arranged to permit flow of airthrough it from the trunk, conduits slidingly supported by said supportin a manner permitting movementy about the axis of the support, saidconduits being in communication with the passage in the support wherebyto admit air, and a .floor arranged between the conduits forming thebottom of the retort of which the conduits are the sides, said conduitshaving air-discharge openings above said floor.

8. In a furnace, the combination of separated conduits having uprightwalls and longitudinal openings in their upper sides, air emissionmembers mounted upon the upper sides of said conduits communicatingtherewith and having outlets at their upper portions, a floor betweenthe conduits exending in such a direction as to intersect the uppersides thereof between the ends of the conduits, and air emission memberssupported by and extending between the conduits in rear of and below.said floor having hollow interiorsin communication with the interior ofthe conduits and having outlets directed toward the ends of theconduits, and said conduits being oscillatively movable about atransverse axisto effect a progression of-fuel.

9. In a furnace, a plurality of fuel retorts extending longitudinally ofthe furnace having mouths opening into the interior of the furnace andeach formed of 'air supplying side walls and a bottom mounted withcapability of oscillation about a horizontal axis transverse to theirlength, means for fo-rcing fuel into the retorts from outside of thefurnace, and mechanism for oscillating adjacent retorts simultaneouslyin opposite directions, whereby to effect a progressive fuel 10. In afurnace, a fuel-burning retort extending into the furnace inclosure andhaving a bottom and side walls, the upper limitsof which are inclined toform a downwardly sloping mouth, means for supporting said retort nearits uppermost and forward end with capability of oscillating about ahorizontal axis transverse to the longitudinal dimensions of thefurnace, means for feeding fuel into the lretort at its supported end,and means for oscillating the retort about its axis to effect aprogressive fuel feed.

11. In a furnace, a fuel burning retort extending into the furnace,constructed with rigidly connected side walls and bottom with a fuelspace between them and having a fuel inlet adjacent to one boundary ofthe furnace, said retort being mounted oscillatively on a horizontaltransverse axis near said boundary, and mechanism for oscillating saidretort continuously to effect a gradual progression of fuel into thefurnace.

12. In a furnace, a fuel burning retort provided with upright walls, asupport therefor having a horizontal axis transverse to the planes ofsaid walls whereon said walls are pivotally mounted, and a fuel pusherarranged to reciprocate between said walls and across said pivotal axis.

13. In a furnace, a fuel burning retort provided with rigidly connectedsides and floor and mounted to oscillate as a unit about a horizontalaxis, a fuel feeder in said retort arranged to reciprocatelongitudinally thereof, and mechanism for oscillating the retort andreciprocating the feeder whereby a progressive feed movement of the fuelfrom the front to the rear of the retort is effected.

14, In a furnace, a fuel burning retort provided with upright walls, asupport therefor located near one end of the walls, having-a transversehorizontal axis on which the walls are mounted with capability ofoscillative movement about such axis, whereby the wall ends remote fromthe axis are enabled to rise and descend and the portions of the wallsnearest the axis may move back and forth, a conduit for fuel openinginto the end of the retort over the axis, and means for feeding fuelthrough said conduit into the retort.

15. In a furnace, a fuel burning retort consisting of a floor, andhollow wallsv secured to said Hoor at opposite sides thereof and risingabove the same, said walls constituting air conduits and having airoutlets in their upper portions, and an air trunk separate from andsupporting the retort, on which the latter is mounted to slide bodilyand oscillatively, the interior of the hollow walls being incommunication with the air trunk whereby to permit flow of air from thelatter to said air outlets.

16. In a furnace, a fuel burning retort consisting of a floor, hollowwalls secured to said floor at opposite sides thereof and rising abovethe same, said walls constituting air conduits and having air outlets intheir upper portions, and an air trunk convex on its upper sidesupporting the retort, the retort having depending walls forming achamber and making sliding contact with the upper part of the air trunk,whereby the retort is enabled to move bodily, and the air trunk andhollow walls or conduits being open to such chamber to permit flow ofair to the outlets.

17. In a furnace, in combination with an air trunk having an opening inits upper side, a fuel burning retort consisting of a floor extendingacross the air trunk and formed with depending walls inclosing a chamberand making sliding contact with the air trunk, conduits havingsubstantially upright walls secured to said floor and having interiorcommunication with said chamber, the conduits extending above the floorto form the sides of the retort and being open at the top, and dischargenozzles mounted upon the tops of said conduits in communicationtherewith having outlets for discharge of air.

18. In a furnace, an air trunk having, upon its upper side,.walls curvedcylindri-. cally and circularly about a horizontal axis, a retortincluding a floor extending across said trunk and resting upon suchwalls, said Hoor having also depending walls inclosing an air chamberand making substantially airtight contact with the first-named walls,and conduits arranged on each side of the floor in rigid connectiontherewith and in communication with said air chamber, the conduitsrising above the floor and forming the walls of the retort andvbeingprovided with air outlets, the entire retort structure being movableslidingly upon the curved walls of the air trunk and being therebycapable of oscillating about the axis of such walls, whereby to effect aprogressive feed of fuel from front to rear.

19. In a. furnace, a retort structure consisting of a fuel conduit orchute and a retort oor extending from said fuel conduit into thefurnace, an air trunk having an with the interior of such chamber. theupper sides of such conduits being open, and nozzle members mounted uponthe upper sides of the conduits in communication therewith and havingair outlets the ventire retort structure being movable bodily withrelation to the air trunk.

20. In a furnace, a retort structure consisting of a fuel conduit orchute and a retort floor extending from said fuel conduit into thefurnace, an air trunk having an opening in its upper side, dependingwalls extending downwardly from the fuel chute andiioor structureinclosing the air trunk opening and making sliding contact with thetrunk, the walls of the trunk with which such contact is made beingcurved concentrically with the horizontal axis, and conduits connectedto said depending walls and having interior communication with the spaceinclosed by said walls, located at the sides of the floor and risingabove the same to form the sides of the retort, said conduits havingoutlets above the plane of the floor.

21. In a furnace, a fuel burning retort eX tending into the furnace anda fuel conduit connected to said retort extending outwardly from thefurnace'. said retort and conduit forming a unit structure and beingpivotally mounted between the ends of such structure,

a fuel feeder mounted reciprocatively in the transverse to its length, afuel pusher arranged to reciprocate in said retort, a slotted erossheadconnected to the pusher` and a rotating driving crank in said slottedcrosshead adapted to move the pusher reciprocatively and at the sametime oscillate the retort.

24. In a furnace, the combination with an oscillatively-niounted fuelburning retort and a pusher for feeding the fuel arranged to reciprocatein said retort transversely to the axis about which the latteroscillates. of driving mechanism constructed to reciprocate the pusherand simultaneousl)v oseillate the retort, and adjusting means wherebythe extent of oscillative, movement imparted to the retort may bcvaried.

25. In a furnace, a fuel burning retort mounted with provision formovement bodily in opposite directions, a fuel feeder mounted toreciprocate longitudinally7 in said retort. and mechanism for so movingthe pusher and the retort, said mechanism including means for varyingthe extent of movement of the retort.

QG. In a furnace, the combination with an oscillatively mounted fuelburning retort and a fuel-feeding pusher reciprocating longitudinally insaid retort, of a driving crank, and a slotted crosshead secured to thepusher transversely thereof in which the crank is contained, the slot ofsaid crosshead being shorter than the throw of the crank. whereby thelatter actuates both the pusher and retort.

Q7. In a furnace, the combination with an oscillat-ively mounted fuelburning retort and a fuel-feeding pusher reciprocating longitudinally,in said retort, of a driving crank, a slotted crosshead secured to thepusher transversely thereof in which the crank is contained, the slot ofsaid crosshead being shorter than the throw of the crank whereby thelatter actuates both the pusher and retort. and an adjustable abutmentin such slot adapted to be moved so as to vary the effective length ofthe slot and thereby control the extent of oscillative movement im- Yparted to the retort.

Q8. In a furnace, the combination of a plurality of fuel feeding andburning retorts mounted side by side in parallel relation and eachmovable in opposite directions, one of such directions being opposed tothe force of gravity, driving mechanism for so moving one of saidretorts, and connections between the retorts whereby the force ofgravity upon either tends to move the other in the direction opposed togravitation.

29. In a, furnace, the combination of two or more fuel feeding andburning retorts arranged in arallel relation adapted to move opposite yto one another in such directions as to be alternately assisted andopposed by the force of gravity, and connection between adjacent retortsthrough which the force of gravity acting upon one tends to ilove theother in the gravity-opposing direction.

30. In a furnace, the combination with an air trunk having parallelupright walls with their outer edges circularly curved, of separated airconduits having outlets and provided with upright walls in the planes ofthe first-named walls and having circular concavities to receive same,the conduit i 'alls being adapted to slide on the other walls, wherebythe conduits may oscillate about the center of curvature of such edges.and means for feeding fuel into the space between said conduits.

3l. In a furnace, a fuel retort comprising a bottom and side wallsrising above said bottom and having provisions for emitting air to fuelin the retort,` said walls being lll) mounted with capability for up anddown movement at their rear ends, means for feeding fuel into theforward end of the retort, and means for giving the defined movement tosaid walls to effect a further progression of the fuel and refuse in theretort.

32. In a furnace, a fuel burning retort extending from the front towardthe rear of the furnace and composed essentially of a bottom and sidewalls, the side walls being mounted to oscillate about an a-Xis soplaced that the rear ends of the walls move up and down and theirforward ends move back and forth, means for feeding fuel into theforward end of the retort, and means for oscillating said walls, wherebyto effect a further movement of the fuel in the retort.

33. In a furnace, a fuel burning retort having a bottom and side Wallsconnected together into a unit structure, means for charging fuel intoone end of the retort, and meansfor oscillating the retort about atransverse horizontal axis beneath the admission end of the retort topropel farther' the material therein.

34. In a furnace, a plurality of fuel burning retorts arranged side byside, each haying a bottom and side walls, means for feeding fuel intothe retorts, and means for oscillating the walls of adjacent retortssimultaneously and in relatively opposite directions about an axis soplaced that the walls of one retort are raised while the walls of theadjacent retort are lowered, and the reverse, whereby a further feedingand distribution of the fuel in and over the retorts is effected.

In a furnace, a plurality ofair conduits arranged side by side withintermediate spaces to provide fuel burning retorts, plates between saidconduits forming the bottoms of said retorts, air emission means mountedon said conduits in series extending longitudinally thereof, incommunication with the interiors of the conduits on which they arerespectively mounted, and arranged to direct air across the retorts,means for feeding fuel into the retorts, and means for oscillating theair conduits about an axis so placed that the rear ends of the conduitsare alternately raised and lowered, one conduit being thus raised whileanother is lowered, whereby to progressively advance the fuel and refusein the furnace.

In testimony whereof Il have aiiixed my signature, in presence of twowitnesses.

ROBERT SANFORD RILEY. Witnesses ARTHUR H. BURNS, I. W. PEZZETTL Copiesof this patent may be obtained for five cents each, by addressing theCommissioner of Patents, Washington, D. C.

